The present invention is concerned with coating processes, particularly those utilizing high-solids alkyd paints.
In order to minimize the amount of solvent required in coating compositions, most of which is released to the atmosphere during painting operations, it is desirable to produce coating compostions having relatively small amounts of solvents and relatively large amounts of solids. The time and energy required to cure such coatings are important parameters.
Alkyd paints are relatively inexpensive, and it would be desirable to have a high-solids, alkyd-based paint which could be cured at low temperatures in a short period of time. U.S. Pat. No. 4,014,830--Rumfield (Mar. 29, 1977), assigned to Celanese Coatings and Specialities Company uses up to 10 weight percent of a polyacrylate or polymethacrylate ester of a polyol as as a modifier in an alkyd resin to allegedly speed up the through-dry of the coatings and to permit obtaining harder films after overnight drying. Although methacrylates are mentioned, the disclosure focuses on acrylates including trimethylol propane triacrylate. Similar technology using 0.1 to 10% monomer is disclosed in French Patent Publication 2,312,302 (1976), assigned to Societe Continentale Parker, and corresponding Belgian Patent 842,167 (1976).
U.S. Pat. Nos. 3,743,615--Yethon (1973) and 4,049,599--Lott (Sept. 20, 1977) discuss methods of increasing the drying speed or the solids content of paints.
German Offenlegunschrift 2,710,032, published Sept. 9, 1977 and based on two U.S. applications filed Mar. 8, 1976, discloses the use of dicyclopentenyl acrylate or methacrylate as a reactive, nonvolatile monomer in an alkyd resin paint which can also contain a cobalt salt and a volatile ketoxime. However, the (meth)acrylate acid ester of dicyclopentadiene used in that patent has just one acrylic or methacrylic group.
It would be desirable to have a paint which is capable of application with less solvent and curing at a higher speed and lower temperatures than is available from the prior art.